<template>
  <view>
    <!-- 这是自定义的搜索组件 -->
    <!-- <my-search :bgcolor="'pink'" :radius="3"></my-search> -->
    <my-search @click="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左侧滑动区域 -->
      <scroll-view class="left-scroll-view" scroll-y="true" :style="{height: wh+'px'}">
        <!-- 循环渲染结构时,为选中项动态添加.active的类名 -->
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item',i===active?'active':'']"  @click="activeChanged(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
       <!-- 右侧滑动区域 -->
       <scroll-view scroll-y="true" :style="{height: wh+'px'}" :scroll-top="scrollTop">
         <view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
           <!-- 二级分类的标题 -->
           <view class="cate-lv2-title">/{{item2.cat_name}}/</view>
           <!-- 动态渲染三级分类的列表数据 -->
           <view class="cate-lv3-list">
             <!-- 三级分类的item项 -->
             <view class="cate-lv3-item" v-for="(item3,i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
               <!-- 这是三级分类图片 -->
               <image :src="item3.cat_icon"></image>
               <!-- 这是三级分类文字 -->
               <text>{{item3.cat_name}}</text>
             </view>
           </view>
         </view>
       </scroll-view>
    </view>
  </view>
</template>

<script>
  import  badegMix from '@/mixins/tabbar-badge.js'
  export default {
    mixins:[badegMix],
    data() {
      return {
        //当前设备可用的高度
        wh: 0,
        // 分类数据列表
        cateList:[],
        //当前选中项的索引,默认让第一项被选中
        active: 0,
        //二级分类列表
        cateLevel2: [],
        scrollTop: 0
      };
    },
    onLoad(){
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const { data: res } = await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status!==200) return uni.$showMsg()
        this.cateList = res.message
        //为二级分类赋值
        this.cateLevel2 = res.message[0].children
      },
      //选中选项卡
      activeChanged(i){
        this.active=i
        //重新为二级分类赋值
        this.cateLevel2=this.cateList[i].children
        //点击选项卡让scrollTop重置为0
         this.scrollTop = this.scrollTop === 0 ? 1 : 0
         console.log(this.scrollTop)
      },
      //点击三级分类跳转到商品页面
      gotoGoodsList(item3){
         console.log(item3)
         uni.navigateTo({
           url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
         })
      },
      gotoSearch(){
        uni.navigateTo({
          url: '/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
  .scroll-view-container{
    display: flex;
    .left-scroll-view{
      width: 240rpx;
      .left-scroll-view-item{
        background-color: #F7F7F7;
        line-height: 60px;
        text-align: center;
        font-size: 12px;
        // 激活项的样式
        &.active{
          background-color: #FFF;
          position: relative;
          // 渲染激活项左侧的红色指示边线
          &:before{
            content: '';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #C00000;
            position: absolute;
            top: 50%;
            left: 0;
            transform: translateY(-50%);
          }
        }
      }
    }
  }
  .cate-lv2-title{
    font-size: 12px;
    font-weight: 700;
    text-align: center;
    padding: 15px 0;
  }
  .cate-lv3-list{
    display: flex;
    flex-wrap: wrap;
    .cate-lv3-item{
      width: 33.33%;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      margin-bottom: 10px;
      image{
        width: 60px;
        height: 60px;
      };
      text{
        font-size: 12px;
      }
    }
  }
</style>
